My Inquiry
My Account
Texas Instruments LM397MF/NOPB
- Part No.:
- LM397MF/NOPB
- Manufacturer:
- Texas Instruments
- Category:
- Comparators
- Package:
- SC-74A, SOT-753
- Datasheet:
-
LM397MF/NOPB.pdf
- Description:
- IC COMPARATOR 1 GEN PUR SOT23-5
- Quantity:
- Payment:
- Shipping:
Inventory:17,992
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LM397MF/NOPB from Texas Instruments is a single general-purpose voltage comparator with bipolar input stage, open-collector NPN output, and ground-sensing input common-mode range (0 V to VS – 1.5 V). It operates from 5 V to 30 V single or dual supply, draws only 300 µA supply current at 25°C, and delivers 440 ns propagation delay (50-mV overdrive) - enabling fast threshold detection in industrial sensor interfaces and A/D converter front-ends.
For engineers reviewing the LM397MF/NOPB datasheet, LM397MF/NOPB pinout, LM397MF/NOPB application, or LM397MF/NOPB equivalent, key selection considerations include its SOT-23 (DBV) 5-pin package, ±2 mV input offset voltage, 7 nA input bias current, open-collector output requiring external pull-up, and −40°C to +85°C industrial temperature range.
Technical Context
The LM397MF/NOPB implements a bipolar-input comparator architecture with rail-to-rail input common-mode capability down to ground, allowing direct sensing of low-side signals without level-shifting. Its open-collector output stage supports logic-level translation via externally selected pull-up voltage and enables wired-OR configurations.
It features low input bias (7 nA typ.) and offset currents (±1 nA), enabling high-impedance source interfacing, while maintaining stable performance across 5–30 V supply range - supply current varies only from 0.25 mA to 0.3 mA over that range. Propagation delay is overdrive-dependent, ranging from 440 ns (50 mV) to 940 µs (5 mV).
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Supply Voltage Range | 5 V to 30 V - supports wide-range industrial power rails and eliminates need for dedicated low-voltage regulators. |
| Input Offset Voltage | ±2 mV (typ.) - enables accurate threshold detection within ~2 mV tolerance without trimming. |
| Supply Current | 300 µA (typ. at 25°C) - allows battery-backed or low-power monitoring circuits with minimal quiescent load. |
| Propagation Delay | 440 ns (50-mV overdrive) - ensures sub-microsecond response for pulse-width or zero-crossing detection. |
| Input Bias Current | 7 nA (typ.) - permits use with high-impedance sources (e.g., thermistors, photodiodes) without significant error. |
| Common-Mode Input Range | 0 V to VS – 1.5 V - allows direct ground-referenced signal comparison without input level-shifting circuitry. |
| Output Type | Open-collector NPN - enables flexible logic interfacing (TTL/CMOS), wired-OR outputs, and programmable output voltage via external pull-up. |
Pinout & Package
LM397MF/NOPB is housed in a 5-pin SOT-23 (DBV) package measuring 2.90 mm × 1.60 mm × 1.45 mm max height, optimized for space-constrained PCB layouts and compatible with standard pick-and-place assembly.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| VIN− (Pin 1) | Inverting Input | Accepts reference or threshold voltage; comparator output goes low when VIN− exceeds VIN+ by > VOS. |
| GND (Pin 2) | Ground Reference | System ground return; required for single-supply operation and defines 0-V reference for inputs and output saturation. |
| VIN+ (Pin 3) | Noninverting Input | Accepts sensed signal; output goes high when VIN+ exceeds VIN− by > VOS - supports ground-referenced inputs. |
| OUTPUT (Pin 4) | Open-Collector Output | Sinks up to 13 mA; requires external pull-up resistor to define logic-high voltage and drive load (e.g., microcontroller GPIO or LED). |
| VS (Pin 5) | Positive Supply | Connects to 5–30 V supply; powers internal circuitry and serves as pull-up target for output stage when used in single-supply mode. |
Key Features
| Feature | Design Value |
|---|---|
| Ground-sensing input stage | Enables direct comparison of 0-V-referenced signals (e.g., current-sense shunt, battery monitor) without input biasing networks. |
| Open-collector output | Permits level translation across logic families (e.g., 3.3-V MCU interface with 12-V pull-up) and supports multi-comparator wired-OR alarm buses. |
| Wide supply range (5–30 V) | Eliminates need for separate voltage regulators in mixed-rail systems - operates identically from 5-V USB-powered boards to 24-V industrial PLCs. |
| Low 300-µA quiescent current | Supports always-on monitoring in energy-sensitive applications such as battery-operated sensors or backup power supervisors. |
| Industrial temperature range | Guarantees parametric performance from −40°C to +85°C - suitable for uncontrolled environments like factory floors or outdoor enclosures. |
Applications
| Overvoltage Protection Circuit | Zero-Crossing Detector |
|---|---|
|
Use Scenario: Monitoring DC bus voltage in motor drives to trigger shutdown before capacitor overvoltage. IC Role / Device Role / Timing Role: Voltage comparator comparing sensed bus voltage against fixed reference; asserts fault signal on overvoltage event. Use Value: Fast 440-ns response ensures protection activation within microseconds of overvoltage onset, preventing capacitor degradation. |
Use Scenario: Detecting AC line zero crossings for phase-controlled dimming or synchronous rectification. IC Role / Device Role / Timing Role: Comparator comparing AC waveform against 0-V reference; generates clean digital edge at each polarity transition. Use Value: Ground-sensing input allows direct connection to center-tapped transformer or resistive divider without offset compensation. |
| Thermistor-Based Temperature Threshold | ADC Input Conditioning |
|
Use Scenario: Activating cooling fan when thermistor voltage crosses preset threshold in embedded thermal management. IC Role / Device Role / Timing Role: Single-supply comparator converting analog thermistor divider output into on/off control signal. Use Value: 7-nA input bias avoids loading high-resistance thermistor networks, preserving measurement accuracy. |
Use Scenario: Providing precise start-of-conversion trigger for successive-approximation ADCs based on analog input crossing reference. IC Role / Device Role / Timing Role: High-speed comparator generating clean, jitter-free conversion-start pulse synchronized to analog threshold crossing. Use Value: 440-ns propagation delay minimizes timing uncertainty between analog event and ADC sampling initiation. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar voltage comparator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TL331IDBVR | Pin-compatible SOT-23 single comparator; identical pinout and electrical specs, but rated for −40°C to +125°C. | Preferred for automotive under-hood or extended-temperature industrial use where 85°C upper limit is insufficient. | Select TL331IDBVR when operating above +85°C or requiring AEC-Q200 qualification support. |
| LMV331IDBVR | Rail-to-rail input/output CMOS comparator; lower supply current (17 µA), wider supply range (2.7–5.5 V), but no ground-sensing input. | Better suited for low-voltage portable electronics; cannot directly replace LM397MF/NOPB in ground-referenced or >5.5-V applications. | Choose LMV331IDBVR only for 3.3-V systems requiring ultra-low power and rail-to-rail output swing - not a drop-in replacement. |
Compared with TL331IDBVR, LM397MF/NOPB offers identical functionality at lower cost for industrial ambient conditions, while LMV331IDBVR trades ground-sensing capability and voltage range for nanoscale power efficiency in battery-powered designs.
Availability
LM397MF/NOPB is available at Aetrix Electronics and suitable for industrial sensor interfaces, power supply monitoring, and A/D converter triggering requiring stable component supply across long-lifecycle embedded programs.
Supply support for LM397MF/NOPB includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
Texas Instruments is a global semiconductor leader delivering analog, embedded processing, and connectivity solutions for industrial, automotive, and personal electronics markets.
The LM397MF/NOPB belongs to TI's general-purpose analog comparator product line, designed specifically for cost-sensitive, robust industrial signal conditioning where ground-referenced sensing and wide supply flexibility are essential.
FAQ
What is the maximum supply voltage rating for LM397MF/NOPB?
The absolute maximum supply voltage for LM397MF/NOPB is 30 V, with recommended operating range specified from 5 V to 30 V. Exceeding 30 V risks permanent damage per Absolute Maximum Ratings. At 30 V operation, supply current remains within 0.3 mA typical, and output sink capability holds at ≥6 mA - making LM397MF/NOPB suitable for 24-V industrial control rails without derating.
Does LM397MF/NOPB support true ground-referenced input operation?
Yes, LM397MF/NOPB supports true ground-referenced input operation: its input common-mode voltage range extends down to 0 V (GND) across the full −40°C to +85°C temperature range. This allows direct connection of VIN+ or VIN− to ground-referenced signals - such as shunt-based current sensing or thermistor dividers - without external level-shifting circuitry, a key differentiator from many rail-to-rail comparators.
What pull-up resistor value should be used with LM397MF/NOPB's open-collector output?
A 5.1-kΩ pull-up resistor to VS is commonly used with LM397MF/NOPB for 5–30 V supplies, balancing speed (CL = 15 pF yields 440 ns tPLH at 50-mV overdrive) and power (0.6–1.8 mW dissipation). For higher-speed loads, reduce to 1–2.2 kΩ; for ultra-low power, increase to 10–100 kΩ - ensuring output sink current stays below 13 mA and VOL remains ≤400 mV at 25°C per datasheet limits.
Can LM397MF/NOPB be used in dual-supply configurations?
Yes, LM397MF/NOPB supports dual-supply operation with ±15 V maximum total supply (VS+ to VS−), as confirmed in Absolute Maximum Ratings. In dual-supply mode, GND (Pin 2) becomes the reference node, VIN+ and VIN− accept inputs from −15 V to +13.5 V (VS+ – 1.5 V), and OUTPUT sinks current toward VS−. This configuration enables symmetric signal handling in audio or precision instrumentation applications.
Is LM397MF/NOPB RoHS compliant and lead-free?
Yes, LM397MF/NOPB is RoHS compliant and lead-free, with Sn (tin) lead finish and MSL Level-1 rating (260°C peak reflow, unlimited floor life). The "NOPB" suffix explicitly denotes lead-free packaging per TI's ordering nomenclature, and the device meets JEDEC J-STD-020 moisture sensitivity requirements for standard surface-mount assembly processes.
LM397MF/NOPB Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Package/Case:
- SC-74A, SOT-753
- Series:
- -
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Type:
- General Purpose
- Number of Elements:
- 1
- Output Type:
- Open-Collector, Rail-to-Rail
- Voltage - Supply, Single/Dual (±):
- 5V ~ 30V, ±2.5V ~ 15V
- :
- 7mV @ 30V
- Voltage - Input Offset (Max):
- 0.25µA @ 5V
- Current - Input Bias (Max):
- 13mA @ 5V
- Current - Output (Typ):
- 2mA
- Current - Quiescent (Max):
- -
- CMRR, PSRR (Typ):
- -
- Propagation Delay (Max):
- -
- Hysteresis:
- -40°C ~ 85°C
- Operating Temperature:
- -
- Grade:
- -
- Qualification:
- Surface Mount
- :
- SOT-23-5
LM397MF/NOPB FAQ
1.How can I place an order for LM397MF/NOPB through Aetrix?
Please submit a Request for Quotation (RFQ) for LM397MF/NOPB on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for LM397MF/NOPB reliable?
The price and inventory of LM397MF/NOPB are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LM397MF/NOPB is usually 5 days.
3.What payment methods are accepted for LM397MF/NOPB?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LM397MF/NOPB transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LM397MF/NOPB?
LM397MF/NOPB orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LM397MF/NOPB order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for LM397MF/NOPB?
For technical support, including LM397MF/NOPB datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LM397MF/NOPB requirements.
6.How does Aetrix verify that LM397MF/NOPB is sourced from the original manufacturer or authorized distributors?
All LM397MF/NOPB products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that LM397MF/NOPB meets industry standards.
7.What is the process for return or replacement of LM397MF/NOPB?
All LM397MF/NOPB units undergo pre-shipment inspection (PSI). If there is an issue with LM397MF/NOPB, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The LM397MF/NOPB part is unused and in its original packaging.
Return procedure for LM397MF/NOPB:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LM397MF/NOPB Tags
-
LM2903DR
Texas Instruments
-
LM339DR
Texas Instruments
-
LM339PWR
Texas Instruments
-
LM393DT
STMicroelectronics
-
LM2901PWR
Texas Instruments
-
LM2903DT
STMicroelectronics
-
LM393DR
Texas Instruments
-
LM239DR
Texas Instruments
-
LM339APWR
Texas Instruments
-
LM2903P
Texas Instruments
-
LM393ADR
Texas Instruments
-
NCX2200GMAZ
NXP Semiconductors
Tech Hub
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
